Impact Of Vaccination Research Articles

Modeling the population-level impact of a third dose of MMR vaccine on a mumps outbreak at the University of Iowa

Mumps outbreaks among fully vaccinated young adults have raised questions about potential waning of immunity over time and need for a third dose of the measles, mumps, rubella (MMR) vaccine. However, there are currently limited data on real-life effectiveness of the third-dose MMR vaccine in preventing mumps. Here, we used a deterministic compartmental model to infer the effectiveness of the third-dose MMR vaccine in preventing mumps cases by analyzing the mumps outbreak that occurred at the University of Iowa between August 24, 2015, and May 13, 2016. The modeling approach further allowed us to evaluate the population-level impact of vaccination by different timing in relation to the start of the outbreak and varied coverage levels, and to account for potential sources of bias in estimating vaccine effectiveness. We found large uncertainty in vaccine effectiveness estimates; however, our models showed that early introduction of a third dose of MMR vaccine during a mumps outbreak can be effective in preventing transmission. School holidays, such as the winter break, likely played important roles in preventing mumps transmission.

Effect of The Pfizer-Biontech Vaccine on Ifn-Γ Serum Levels and its Genetic Variations in Response to Vaccination

Background: Pfizer vaccine, which is a nucleoside-modified mRNA vaccine against coronavirus disease 2019 (COVID-19) is one of the first mRNA products to be approved by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). Aim of the study: The aim of this study is to study the impact of Pfizer vaccine on the levels of interferon gamma (IFN-γ) serum levels and its gene polymorphism after 3 months and 6 months of vaccination with Pfizer vaccine . Materials and methods: This case-control study involved (150) subjects who were divided into three groups (each group included 50 subjects). The first group included (50) vaccinated group 3 months after second dose of Pfizer vaccine, and the second group included (50) vaccinated group 6 month after second dose of Pfizer vaccine. The third group was the control group which included (50) healthy unvaccinated subjects. The study was done during the period from May /2022 to September / 2022). Serum levels of IFN-γ were estimated by ELISA technique. The PCR technique was used to study gene polymorphism for IFN-γ. Results: The results in figure (1) showed that the mean levels of INF-γ among the male participants (after 3 months of vaccination, after 6 months of vaccinations, and the control group) were (292.54, 231.48, and 15.71), respectively, with highly significant differences (HS) between the three groups (p<0.01). The results also showed that the mean levels of INF-γ among female participants (after 3 months of vaccination, after 6 months of vaccinations, and the control group) were (317.31, 228.14, and 15.74), respectively, with highly significant differences (HS) between the three groups (p<0.01). Analysis of rs2430561 SNP of (IFN-γ) gene using Sanger sequencing. Single “T” peak indicative of a T homozygous allele showed that Single “A” peak indicative of a A homozygous allele. Presence of the “T” and “A” peak indicative of T/A heterozygous allele. Conclusion: Pfizer vaccine was shown to have significant impacts on IFN-γ levels and presence of single T/A alleles is indicative of heterogeneous T/A allele on analysis of rs2430561 SNP of (IFN-γ) gene among vaccinated individuals.

The potential impact of new TB vaccines on the burden of TB in people living with HIV in South Africa.

People living with HIV (PLHIV) are at increased risk of tuberculosis (TB). New TB vaccines may help reduce this burden. New TB vaccine candidates are safe and immunogenic in PLHIV.There is currently limited data on vaccine efficacy in this population. Using mathematical modelling we explored the potential impact of a novel TB vaccine on TB burden in PLHIV in South Africa between 2030-2050. We compared the impact of a vaccine delivered irrespective of HIV status to vaccination of either PLHIV or people without HIV. We explored the impact of reduced vaccine efficacy and duration of protection in PLHIV relative to people without HIV on our model predictions. Vaccination irrespective of HIV status, with a vaccine with equal efficacy and duration in PLHIV, could avert up to 1.01 (95% range: 0.96-1.22) million TB cases in PLHIV. Restricting vaccination to PLHIV or people without HIV would achieve 65% (60-70) and 48% (46-53) of the total impact respectively. These results are strongly dependent on the assumed efficacy and duration of protection in PLHIV. Further information on these characteristics is important to identify the most efficient use of new vaccines to reduce TB burden in PLHIV. Our results suggest that new vaccines could play an important role in reducing the TB burden in PLHIV. Vaccines targeted at people without HIV individuals could provide significant indirect benefit to PLHIV, but vaccines which are safe and effective in PLHIV will be critical to maximizing the impact in this population.

The impact of COVID-19 vaccination on patients with congenital heart disease in England: a case-control study

BackgroundStudies predating widespread COVID-19 vaccination identified patients with congenital heart disease (CHD) as a group at increased risk of severe outcomes from COVID-19. Here we evaluate the impact of vaccination...

Potential impact of rotavirus vaccine introduction in India’s Universal Immunisation Programme on private sector vaccine utilisation: an interrupted time series analysis

BackgroundDespite free immunisation services through the Universal Immunisation Programme (UIP), around 14% of Indian households seek immunisation in the private sector. We examined the potential impact of rotavirus vaccine (RVV) introduction in the Universal Immunisation Programme (UIP) on private-sector rotavirus vaccine utilisation.MethodsWe analysed nationally representative private-sector vaccine sales data. The intervention under consideration is RVV introduction in the UIP in selected Indian states. The outcome is the ‘monthly RVV sales volume’—a proxy for vaccine utilisation. We performed a Poisson regression interrupted time series analysis to detect the pre-intervention trend, post-intervention level change and trend change relative to the pre-intervention for monthly rotavirus vaccine utilisation.ResultsPoisson segmented regression analysis showed that immediately after RVV introduction in the UIP private-sector RVV sales showed a decline in Rajasthan by 37.4% (Incidence Risk Ratio (IRR): 0.626; 95% CI: 0.504–0.779), in Tamil Nadu by 26% (IRR: 0.740; 95% CI: 0.513–1.068), in Uttar Pradesh-East by 72.2% (IRR: 0.278; 95% CI: 0.178–0.436) and in Kerala by 3% (IRR: 0.970; 95% CI: 0.651–1.447). Rajasthan, Tamil Nadu and Kerala had sustained reduction in the postintervention trend relative to the preintervention trend by 20.1% (IRR: 0.799; 95% CI: 0.763–0.836), 6.4% (IRR: 0.936; 95% CI: 0.906–0.967) and 3.3% (IRR: 0.967; 95% CI: 0.926–0.960) per month, respectively. However, in Haryana and UP-west, in the first-month post-UIP introduction, the private-sector RVV sales increased by 101% and 3.8%, respectively which was followed by a sustained decrease of 14.2% (IRR: 0.858; 95% CI: 0.688–1.070) and 5.8% (IRR: 0.942; 95% CI: 0.926–0.960) per month, respectively. In terms of long-term impact, the private sector RVV sales post-UIP introduction decreased at a monthly rate of 4.4% (IRR: 0.956, 95% CI: 0.939–0.974) in Rajasthan but increased by 5.5% (IRR: 1.055; 95% CI: 1.040–1.070) in UP-east, 0.3% (IRR: 1.003, 95% CI: 0.976–1.031)) in Kerala and 0.2% (IRR: 1.002, 95% CI: 0.993–1.011) in Tamil Nadu whereas Haryana and UP-west had a reduction in RVV utilisation by 2.8% (IRR: 0.972; 95% CI: 0.955–0.990) and 1% (IRR: 0.990; 95% CI: 0.982–0.998), respectively.ConclusionsThe study provides evidence that access to RVV through UIP leads to a reduction in private-sector RVV utilisation. We recommend strengthening UIP to expand the basket of new vaccines.

Impact of Vaccination and the Anti-Vaccine Movement on Health in Brazil recorded in 2018.

Impact of Vaccination and the Anti-Vaccine Movement on Health in Brazil recorded in 2018.

Modeling the impact of screening awareness and vaccination on human papilloma virus transmission

In this work, a two‐sex deterministic model for human papillomavirus (HPV) is developed to assess the impact of screening awareness and vaccination on the transmission dynamics. We provide a detailed analysis of the HPV model and established results for boundedness of the solutions and existence of a positively invariant and attracting set. The basic reproduction number is characterized, and it is shown that the disease‐free equilibrium is locally asymptotically stable if and the system is uniformly persistent if . Sensitivity analysis of reveals that HPV vaccination can mitigate HPV transmission, and HPV vaccination along with screening can further reduce the spread of HPV infection. Numerical simulations showed that the public awareness of screening after being vaccinated is contributing to reduce the spread of epidemic, and the role of screening awareness in controlling the disease was significantly greater among men than women. Besides, the numerical simulations reveal that increasing vaccination rates for male is effective in controlling HPV transmission. Hence, it is necessary to enhance the screening for men. Moreover, increasing vaccination rates is more effective than increasing screening awareness in eliminating the epidemic.

Urban Transportation Measures and Vaccination Impact on The Number of COVID-19 Infections: A Before and After Study

Urban Transportation Measures and Vaccination Impact on The Number of COVID-19 Infections: A Before and After Study

Assessing bull breeding soundness exam parameters following vaccination with modified-live or killed vaccine

Breeding bulls are often placed on a similar herd health plan and vaccinated for the same pathogens as the mature cow herd. The timing of the yearly vaccination is impacted by labor and time constraints with some bulls receiving vaccinations at the time of annual, complete breeding soundness exams or at the time of turnout prior to the breeding season. However, the potential impact of vaccination on spermatogenesis, if any, is unknown. Therefore, the study objective was to determine the impacts on normal sperm morphology through a complete spermatogenic cycle after vaccination of mature beef bulls against bovine herpesvirus 1 and bovine viral diarrhea virus using commercially available modified-live virus (MLV) or killed virus (KV) vaccine. Semen was collected from Bos taurus bulls (n = 11),which were randomly assigned prior to the first breeding soundness exam to vaccine treatment groups: 1) modified-live virus (MLVa); or 2) inactivated/killed virus (KVb). Breeding soundness exams were completed at days -7, 0, 5, 7, 17, 28, 61 following vaccination. No differences were found between vaccine treatment groups MLV and KV (P = 0.46) on the percentage of normal sperm over time (d = -7 through d = 61) as evaluated by two boarded theriogenologists. In conclusion, we found no detrimental effect of the administration of multivalent MLV or KV vaccines on percentage of normal sperm morphology of mature bulls over a 61 – day period.

Using double-debiased machine learning to estimate the impact of Covid-19 vaccination on mortality and staff absences in elderly care homes.

Machine learning approaches provide an alternative to traditional fixed effects estimators in causal inference. In particular, double-debiased machine learning (DDML) can control for confounders without making subjective judgements about appropriate functional forms. In this paper, we use DDML to examine the impact of differential Covid-19 vaccination rates on care home mortality and other outcomes. Our approach accommodates fixed effects to account for unobserved heterogeneity. In contrast to standard fixed effects estimates, the DDML results provide some evidence that higher vaccination take-up amongst residents, but not staff, reduced Covid mortality in elderly care homes. However, this effect was relatively small, is not robust to alternative measures of mortality and was restricted to the initial vaccination roll-out period.

Cost-Effectiveness of Bivalent Respiratory Syncytial Virus PrefusionF (RSVpreF) Vaccine During Pregnancy for Prevention of Respiratory Syncytial Virus Among Infants in Argentina.

Lower respiratory tract illness (LRTI) caused by respiratory syncytial virus (RSV) is common among young children in Argentina. Use of the currently available prophylactic agent is limited to children aged ≤ 2years with selected high-risk conditions, and thus the majority of infants remain unprotected. We estimated the value-based price (VBP) of a novel RSVpreF vaccine for use among pregnant people for prevention of RSV-LRTI among infants during the first year of life. Clinical outcomes and economic costs of RSV-LRTI during infancy and expected impact of RSVpreF vaccination during pregnancy were projected using a population-based Markov-type cohort model. Model results-estimated on the basis of gestational age at birth, disease/fatality rates, and mother's vaccination status-include total numbers of RSV-LRTI cases, RSV-LRTI-related deaths, and associated costs. Base case analyses (RSVpreF vs. no vaccine) were conducted from the healthcare system perspective. Probabilistic sensitivity analyses (PSA; 1000 replications) were also conducted. Willingness-to-pay (WTP) was $10,636 per quality-adjusted life-year (QALY; i.e., 1 × 2021 gross domestic product [GDP] per capita) in base case analyses and PSA. Costs are reported in USD, estimated on the basis of the June 22, 2023 exchange rate. Use of RSVpreF among 342,110 pregnant persons provided protection to 330,079 infants at birth. In total, RSVpreF prevented 3915 RSV hospitalizations, 6399 RSV cases requiring emergency department care, 6182 RSV cases requiring a physician office visit, and 67 disease-related deaths. Direct costs were projected to be reduced by $5.0million. With 2061 QALYs gained and vaccine administration cost of $1.4million, the VBP of RSVpreF was estimated to be $74.46 per dose. In PSA, mean VBP was $75.02 (95% confidence interval 54.24-97.30). RSVpreF among pregnant persons would significantly reduce the clinical and economic burden of RSV-LRTI among infants in Argentina and would be considered a cost-effective intervention up to a price of approximately $75.

COVID-19 Vaccine Impact and Future Threats From Other Pandemics

COVID-19 Vaccine Impact and Future Threats From Other Pandemics

Impact and Effectiveness of COVID-19 Vaccines Based on Machine Learning Analysis of a Time Series: A Population-Based Study.

Background: Although confirmed cases of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been declining since late 2020 due to general vaccination, little research has been performed regarding the impact of vaccines against SARS-CoV-2 in Spain in terms of hospitalizations and deaths. Objective: Our aim was to identify the reduction in severity and mortality of coronavirus disease 2019 (COVID-19) at a nationwide level due to vaccination. Methods: We designed a retrospective, population-based study to define waves of infection and to describe the characteristics of the hospitalized population. We also studied the rollout of vaccination and its relationship with the decline in hospitalizations and deaths. Finally, we developed two mathematical models to estimate non-vaccination scenarios using machine learning modeling (with the ElasticNet and RandomForest algorithms). The vaccination and non-vaccination scenarios were eventually compared to estimate the number of averted hospitalizations and deaths. Results: In total, 498,789 patients were included, with a global mortality of 14.3%. We identified six waves or epidemic outbreaks during the observed period. We established a strong relationship between the beginning of vaccination and the decline in both hospitalizations and deaths due to COVID-19 in all age groups. We also estimated that vaccination prevented 170,959 hospitalizations (CI 95% 77,844-264,075) and 24,546 deaths (CI 95% 2548-46,543) in Spain between March 2021 and December 2021. We estimated a global reduction of 9.19% in total deaths during the first year of COVID-19 vaccination. Conclusions: Demographic and clinical profiles changed over the first months of the pandemic. In Spain, patients over 80 years old and other age groups obtained clinical benefit from early vaccination. The severity of COVID-19, in terms of hospitalizations and deaths, decreased due to vaccination. Our use of machine learning models provided a detailed estimation of the averted burden of the pandemic, demonstrating the effectiveness of vaccination at a population-wide level.

Impact of COVID-19 Vaccination on Racial Disparity in COVID-19 Mortality from a National US Dialysis Provider

Impact of COVID-19 Vaccination on Racial Disparity in COVID-19 Mortality from a National US Dialysis Provider

On a Symmetry-Based Structural Deterministic Fractal Fractional Order Mathematical Model to Investigate Conjunctivitis Adenovirus Disease

In the last few years, the conjunctivitis adenovirus disease has been investigated by using the concept of mathematical models. Hence, researchers have presented some mathematical models of the mentioned disease by using classical and fractional order derivatives. A complementary method involves analyzing the system of fractal fractional order equations by considering the set of symmetries of its solutions. By characterizing structures that relate to the fundamental dynamics of biological systems, symmetries offer a potent notion for the creation of mechanistic models. This study investigates a novel mathematical model for conjunctivitis adenovirus disease. Conjunctivitis is an infection in the eye that is caused by adenovirus, also known as pink eye disease. Adenovirus is a common virus that affects the eye’s mucosa. Infectious conjunctivitis is most common eye disease on the planet, impacting individuals across all age groups and demographics. We have formulated a model to investigate the transmission of the aforesaid disease and the impact of vaccination on its dynamics. Also, using mathematical analysis, the percentage of a population which needs vaccination to prevent the spreading of the mentioned disease can be investigated. Fractal fractional derivatives have been widely used in the last few years to study different infectious disease models. Hence, being inspired by the importance of fractal fractional theory to investigate the mentioned human eye-related disease, we derived some adequate results for the above model, including equilibrium points, reproductive number, and sensitivity analysis. Furthermore, by utilizing fixed point theory and numerical techniques, adequate requirements were established for the existence theory, Ulam–Hyers stability, and approximate solutions. We used nonlinear functional analysis and fixed point theory for the qualitative theory. We have graphically simulated the outcomes for several fractal fractional order levels using the numerical method.

Optimizing tuberculosis control: a comprehensive simulation of integrated interventions using a mathematical model

Tuberculosis (TB) remains a formidable global health challenge, demanding effective control strategies to alleviate its burden. In this study, we introduce a comprehensive mathematical model to unravel the intricate dynamics of TB transmission and assess the efficacy and cost-effectiveness of diverse intervention strategies. Our model meticulously categorizes the total population into seven distinct compartments, encompassing susceptibility, vaccination, diagnosed infectious, undiagnosed infectious, hospitalized, and recovered individuals. Factors such as susceptible individual recruitment, the impact of vaccination, immunity loss, and the nuanced dynamics of transmission between compartments are considered. Notably, we compute the basic reproduction number, providing a quantitative measure of TB transmission potential. Through this comprehensive model, our study aims to offer valuable insights into optimal control measures for TB prevention and control, contributing to the ongoing global efforts to combat this pressing health challenge.

Mass screening of hepatitis B and C in Burkina Faso: seroprevalence update and impact of hepatitis B vaccine.

Updated data on the seroprevalences of hepatitis B and C viruses (HBV, HCV) are required to enable the adaptation of control strategies. In this study, we aimed to: (i) estimate the seroprevalences of HBsAg carriers and HCV exposure in the general population, and (ii) determine the impact of vaccination on HBV circulation since its introduction in 2006 in the Expanded Program on Immunization (EPI). From October 2020 to October 2022, a mass screening campaign was conducted in 10 cities across Burkina Faso. Individuals of all ages and genders who consented to participate were screened for viral markers (HBsAg, anti-HCV) using rapid diagnostic tests. The proportions of HBsAg carriers and HCV exposure were calculated using Stata, and logistic regression was used to assess the impact of HBV vaccination on HBsAg carriage. A total of 15,650 participants were enrolled in the study. Of these, 51.4% were women and the age range was from 1 to 97 years. All participants were screened for HBsAg and 7,507 were also screened for anti-HCV. Overall, the seroprevalence of HBsAg was 8.8% and 2.6% for anti-HCV. The results indicated that age, gender, and place of residence were associated with HBV infection. The prevalence of HBV and HCV infections remains high in Burkina Faso. Prevention strategies, including initial mass screening with rapid diagnostic tests and vaccination, need to be intensified.

Impact of COVID-19 Vaccination on Fatality and Intensive Care Unit Admission in Patients with Type 2 Diabetes Mellitus

Impact of COVID-19 Vaccination on Fatality and Intensive Care Unit Admission in Patients with Type 2 Diabetes Mellitus

Evaluation of C-C Motif Chemokine Receptor 5 (CCR5) as a Sample Adequacy Control in HPV Molecular Diagnostics.

Background: Reliable Human Papillomavirus (HPV) testing and genotyping are essential for quality assurance in HPV-based primary screening, disease management and for monitoring the impact of HPV vaccination. The clinical validation of HPV molecular diagnostic assays has significantly contributed to these objectives; however, little emphasis has been placed on assuring sample quality. This study aimed to evaluate the accuracy of sample cellularity assessment using the C-C Motif Chemokine Receptor 5 (CCR5) gene target as a marker of sample adequacy in molecular diagnostics. Methods: Jurkat cell line samples were counted using both a Thoma cell-counting chamber and Fluorescence-Activated Cell Sorting (FACS). Jurkat cell line samples at three different concentrations were subsequently evaluated using the OncoPredict HPV Quality Control (QC) real-time PCR assay, employing CCR5 for molecular cellularity quantification. Results: The cellularity values obtained were comparable across the three different methods for all dilutions of the cell line tested. Conclusions: The results obtained from this study show that CCR5 represents a promising molecular marker for the accurate quantification of sample cellularity, confirming its use as a reliable sample adequacy control, thus reducing the risk of "false-negative" results.

Lung damage in SARS-CoV-2 patients: An autopsy study in the era of vaccination.

The contribution of SARS-CoV-2 infection on lung damage and the effect of vaccination on either containing the number of deaths or mitigating lung damage has not been systematically investigated. Post-mortem analysis was performed among consecutive in-patients with COVID-19 deceased in the Province of Trieste (2020-2022). The outcomes of the study were (i) rates of in-hospital mortality, (ii) contribution of COVID-19 to death, (iii) histological extent of lung injury and (iv) impact of vaccination. A total of 1038 consecutive hospitalized patients who died with SARS-CoV-2 infection were autopsied and deep histological analysis of the lungs was performed in a randomly selected sample of 508 cases. Among them, SARS-CoV-2 infection was (a) the cause of death (n = 90), (b) contributing to death (n = 304) and (c) an accompanying feature (n = 114). The incidence of SARS-CoV-2 infection as the primary cause of mortality decreased over time (23.8% in 2020, 20.9% in 2021 and 7.9% in 2022). On multivariable analysis, vaccination (any dose) was independently associated with lower rates of death related to SARS-CoV-2 infection (HR .15, p < .001), after adjusting for other independent predictors. A total of 172 patients were vaccinated at least with two doses at the time of death: 93% triple-vaccinated, 7% double-vaccinated. On histological analysis, vaccinated patients had a greater frequency of pneumonia severity score 0 and 1 (20.3% vs. 5.4% and 20.9% vs. 7.7%, p < .001, respectively), and a substantially lower proportion of pneumonia severity score 3 (26.2% vs. 55.1%, p < .001) compared to unvaccinated patients. COVID-19 vaccination has substantially reduced rates of death related to SARS-CoV-2 infection over time and may have the ability to mitigate lung damage.